In many cellular applications, the battery life of subscriber units such as portables or transportables is a prime concern. Some cellular systems, such as the GSM (Groupe Special Mobile) Digital Cellular System, support "discontinuous receive" (DRX) a feature whereby pages, or calls to subscriber units, are uniformly broken into different groups and broadcast over the air at specific intervals. This mechanism allows mobiles which are not presently in use to "sleep" when pages to it are not being broadcast. The larger the number of groups the pages are broken into, the longer the period that a mobile can sleep before needing to awaken in order to check for pages that may be destined for it. This mechanism is limited, however, in that the largest number of paging groups (which correspond to the greatest battery savings) introduce the largest amount of delay into the system paging response time. Likewise, the configuration that introduces minimum system response delay also corresponds to the greatest level of standby battery consumption.
Thus, the need exists for a radiotelephone system which compromises between the opposing constraints of battery drain and system response delay.